A fuel cell electrolyzer is a device that operates in one direction as a fuel cell and in an opposite direction as an electrolyzer. A fuel cell uses a fuel and an oxidant separated by an electrolyte to produce electricity, while an electrolyzer utilizes input voltage across an electrolyte to separate a chemically bonded compound. Fuel cell electrolyzers may be used to produce and store energy. For example, the electrolysis of water may be used to create hydrogen and oxygen for storage. The hydrogen and oxygen may then be used as reactants to produce electricity.
Fuel cell electrolyzers require thermal management in order to maintain desired performance and avoid damage to the cell. As an example, a solid oxide electrolyzer (SOEL) may operate in endothermic or exothermic mode. In endothermic mode, the SOEL operation requires less electricity to drive the production of hydrogen and oxygen, but an external heat source is required to maintain the temperature and a stable reaction. In exothermic mode, the reaction is stable and self-sustaining, but the SOEL produces heat as a waste product, which decreases the efficiency of the reaction. The waste heat must be removed since continued exothermic operation without cooling will increase the cell temperature until the SOEL fails. Conventionally, the waste heat is removed through the use of a thermal management system.
Typical thermal management systems can include active or passive cooling loops such as a pulsating heat pipe within the electrolyzer system, or a recirculating reactant flow through the cell to remove excess heat. In either case, typical thermal management systems add hardware to the electrolysis process, which can impact overall system efficiency, reliability, power consumption, and weight. When fuel cell electrolyzers are used in certain applications such as to provide power to an airborne vehicle or vehicle system, efficiency, reliability, power consumption, and weight are primary considerations.
It is with respect to these considerations and others that the disclosure made herein is presented.